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1.
熵代表无序的水平,作者使用通气的熵变(ECV)指示肺通气的不均匀性,ECV定义为当前泡潮气量趋近于零时每摩尔被吸入气体从不均匀通气到均匀通气的熵变的极限。本文从熵的基本公式民地出ECV的计算方程。用几个数学模型肺将ECV同其他7个洗出指标进行了比较。8个指标中,只有ECV仅取决于通气分布,其他7个指标不仅取决于通气分布,还同潮气量和死腔的大小有关。这影响了它们评价肺通气不均匀性的效果,ECV的另一  相似文献   
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Treatment of non-seminomatous testicular cancer often leadsto infertility due to anejaculation/retrograde ejaculation andpoor sperm quality. In these men spermatozoa may be obtainedby transrectal electroejaculation (TE), but the optimal strategyfor assisted procreation in these couples is not known. Ouraim was to examine whether TE and conventional in-vitro fertilization(IVF) would be successful. A total of 10 couples, with long-standinginfertility due to anejaculation or retrograde ejaculation aftertreatment for testicular cancer 5–14 years earlier, werereferred to our unit. All men underwent diagnostic TE undergeneral anaesthesia. Spermatozoa were recovered in nine cases.The antegrade fraction was prepared and used for IVF. Spermquality was variable and conventional IVF was considered impossiblein three cases. Altogether six IVF treatment cycles in six couplesresulted in five pregnancies, of which four resulted in a deliveryand one resulted in a spontaneous abortion. One additional pregnancyis ongoing after transfer of cryopreserved embryos. The fertilizationrate was 54% (33/61) and the cleavage rate was 97% (32/33).No complications relating to the procedure have been encountered.  相似文献   
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Abstract The inflammatory response of immune cells to target cells and cell-matrix molecules is regulated by several receptor-ligand molecules. As fibrosis develops in ongoing chronic rejection after liver transplantation, it is of interest to analyze patterns of integrin receptors and cell-matrix molecules in order to study the relation between immune cells and the stromal and parenchymal cells. In the present study, we demonstrated the expression of these molecules in chronic rejected human liver grafts using immunohistochemical techniques. The results showed a differential expression and induction of integrin receptors and cell-matrix molecules on resident liver cells, especially on sinusoids, reflecting a state of chronic inflammation and a specific interaction between integrin receptors and cell-matrix molecules. The patterns of induced integrin receptors on graft-infiltrating cells was closely related to the local production of cell-matrix molecules and reflected the final sequence of a stepwise progress of the inflammatory reaction.  相似文献   
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Background

Cardiovascular disease (CVD) risks are of concern among immigrants and refugees settling in affluent host countries. The prevalence of CVD and risk factors among Somali African immigrants to the U.S. has not been systematically studied.

Methods

In 2015–2016, we surveyed 1156 adult Somalis in a Midwestern metropolitan area using respondent-driven sampling to obtain anthropometric, interview, and laboratory data about CVD and associated risk factors, demographics, and social factors.

Results

The prevalence of diabetes and low physical activity among men and women was high. Overweight, obesity, and dyslipidemia were also particularly prevalent. Levels of calculated CVD risk across the community were greater for men than women.

Conclusion

Though CVD risk is lower among Somalis than the general U.S. population, our results suggest significant prevalence of risk factors among Somali immigrants. Comparison with prior research suggests that CVD risks may be increasing, necessitating thoughtful intervention to prevent adverse population outcomes.

  相似文献   
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Among 33 patients with endocrine pancreatic tumors due to multiple endocrine neoplasia type 1 (MEN-1), 19 (58%) patients had hypergastrinemia, 7 (21%) patients had hyperinsulinism, and 7 (21%) patients had clinically non-functioning lesions. At least one gross tumor was found in all patients undergoing pancreatic surgery, including those with negative localization studies prior to operation. The patients also had additional macroscopic tumors as well as numerous microadenomas, and the lesions frequently were positive for immunostaining with multiple hormones, mainly pancreatic polypeptide, insulin, glucagon, and somatostatin. Duodenal endocrine lesions were found in 4 of 5 investigated patients and stained with gastrin and somatostatin antibodies. Distal, mainly subtotal pancreatic resection, was performed in 18 patients, eventually combined with caput tumor enucleation or duodenotomy, while a few patients underwent only tumor enucleation or a Whipple procedure. The long-erm outcome of operation was most favorable in patients with hyperinsulinism; only 1 patient had clinical recurrence. Patients with hypergastrinemia experienced only transitory lowering of serum gastrin values after pancreatic surgery and 47% of them had or developed metastases. Such tumor spread was seen in 57% of the patients with non-functioning lesions. Nine patients died from progressive tumor disease during follow-up. Consistent with previous studies, we found that surgery is indicated in MEN-1 patients with hyperinsulinism even if a lesion is not visualized by radiology. In addition, these indications should be extended to also include patients with only biochemical markers of disease, including elevations of gastrin, as these indicate the presence of gross tumors. This strategy should be applied especially in patients with aggressive family histories to possibly reduce the risk of malignant tumor progression.
Resumen Entre 33 individuos con tumores pancréaticos endocrinos como componente del síndrome de neoplasia endocrina múltiple tipo 1 (NEM-1), 19 pacientes (58%) tenían hipergastrinemia, 7 (21%) hiperinsulinismo y 7 (21%) lesiones clínicas no funcionantes. En la totalidad de los pacientes sometidos a cirugía pancreática fue hallado por lo menos un tumor, incluso en aquellos con examenes de localización negativos anteriores a la operación. Estos pacientes también albergaban tumores macroscópicos, así como numerosos microadenomas; con frecuencia las lesiones demostraron inmunocoloración con diferentes hormonas, principalmente polipéptido, insulina, glucagón y somatostatina. Se encontraron lesiones endocrinas duodenales en 4 de cada 5 pacientes investigados, las cuales colorearon con gastrina y anticuerpos a la somatostatina. Se practicó resección pancreática distal (principalmente resección subtotal) en 18 pacientes, eventualmente combinada con enucleación del tumor (cuando éste se hallaba ubicado en la cabeza del páncreas) o duodenectomía; solamente unos pocos pacientes fueron sometidos a simple enucleación del tumor o al procedimiento de Whipple. El resultado a largo plazo fue más favorable en los pacientes con hiperinsulinismo, puesto que sólo uno presentó recurrencia clínica. Los pacientes con hipergastrinemia exhibieron apenas una disminución transitoria de los valores de gastrina sérica luego de la cirugía pancreática. Cuarenta y siete por ciento del conjunto tuvo o desarrolló metástasis, en tanto que la extensión local del tumor se presentó en 57% de los casos con lesiones no funcionantes. Nueve pacientes murieron por progresión de la neoplasia en el curso del seguimiento. En acuerdo con sugerencias previas, se considero quo la cirugía está indicada en pacientes con NEM-1 e hiperinsulinismo, aún en los casos en que no se visualiza radiológicamente la lesión, pero que la indicación puede ser ampliada para incluir también pacientes con sólo marcadores bioquímicos, tales como niveles elevados de gastrina, indicativos de la presencia de tumores macroscópicos. Esta estrategia debe ser aplicada principalmente en aquellos pacientes con historia familiar agresiva, con lo cual tal vez se reduce el riesgo de progesión maligna del tumor.

Résumé Parmi 33 patients ayant une tumeur pancréatique endocrine due à une néoplasie endocrine multiple de type 1 (MEN-1), 19 (58%) avaient une hypergastrinémie, 7 (21%) un hyperinsulinisme et 7 (21%) une lésion cliniquement muette. On a mis en évidence au minimum une grosse tumeur chez tous les patients, y compris chez ceux dont les examens préopératoires de dépistage tumoral étaient négatifs. Les patients étaient également porteurs de tumeurs macroscopiques et de nombreux microadénomes. Les lésions montraient souvent un immunomarquage positif pour de multiples hormones, principalement le polypeptide pancréatique, l'insuline, le glucagon et la somatostatine. Des lésions endocrines duodénales furent retrouvées chez 4 des 5 patients explorés; elles montraient un immunomarquage avec les anticorps angigastrine et anti-somatostatine. Une résection pancréatique distale, le plus souvent subtotale, a été réalisée chez 18 patients. Elle était éventuellement complétée par une énucléation tmorale de la tête ou par une duodénotomie. Peu de patients ont bénéficié d'une simple énucléation ou d'une intervention de Whipple. L'évolution postopératoire à long terme a été plus favorable en cas d'insulinome puisque seul un patient a eu une récidive clinique. Les patients atteints de gastrinome n'ont présenté que transitoirement une diminution des taux sériques de gastrine après la chirurgie pancréatique. Quarante sept pour cent de ces patients avaient ou ont développé des métastases contre 57% des patients porteurs de lésions sans traduction clinique. Neuf patients sont décédés en raison de l'extension tumorale au cours du suivi. Conformément à des suggestions antérieures, la chirurgie semble indiquée chez les patients atteints de MEN-1 avec hyperinsulinisme même si la radiologie ne visualise pas de lésion. Mais cette indication peut être élargie aux patients dont seuls les paramètres biologiques sont en faveur d'une grosse tumeur (dont l'hypergastrinémie). Cette stratégie pourrait convenir particulièrement aux patients ayant des antécédents familiaux importants; elle permettrait peut-être de réduire le risque d'extension tumorale.


Presented at the International Association of Endocrine Surgeons in Stockholm, Sweden, August, 1991.  相似文献   
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Daptomycin β-Lactam combination therapy offers “protection” against daptomycin non-susceptibility (DNS) development in Enterococcus faecium. We report failure of this strategy and the importance of source control. Mutations were detected in the LiaF and cls genes in DNS isolates. A single DNS isolate contained an unrecognized mutation, which requires confirmation.  相似文献   
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Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited heart rhythm disorder characterized by the occurrence of potentially life-threatening polymorphic ventricular tachyarrhythmias in conditions of physical or emotional stress. The underlying cause is a dysregulation in intracellular Ca handling due to mutations in the sarcoplasmic reticulum Ca release unit. Recent experimental work suggests that sinus bradycardia, which is sometimes observed in CPVT patients, may be another primary defect caused by CPVT mutations. Herein, we review the pathophysiology of CPVT and discuss the role of sinus node dysfunction as a modulator of arrhythmia risk and potential therapeutic target.  相似文献   
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